Oseberg Power Outage Causes Gas Leak. Production Shut Down

On Thursday afternoon, 14 March, there was a power outage on board the Oseberg field centre in the Norwegian part of ther North Sea, Statoil has reported. The power outage led to a gas leak, which has been stopped. The field centre has subsequently experienced additional power supply problems.

Well operations were underway on Oseberg B, and the power outage caused a gas leak from the well where work was in progress.

The facility was shut down in accordance with procedures, the emergency response organisation was mobilised, and the people on board mustered to the lifeboat stations. The onshore emergency response organisation was also mobilised. Power was restored by 18.30, the gas leak was stopped and the situation was gradually returned to normal.

During the subsequent start-up of the facility, gas detectors on Oseberg A indicated that gas was present. The alarm was triggered again just after midnight. The facility was depressurised and personnel mustered to the lifeboats. The gas detectors quickly returned to normal levels, and the situation was resolved without further mobilisation of the emergency response organisation.

Following this, the Oseberg field centre experienced another power failure, with loss of main power. It took some time to re-establish the main power supply. During this period, the emergency power unit on board handles the emergency preparedness systems, provides light and limited communications. Measures were also initiated to safeguard the personnel on board, as the heating unit was not in operation.

Floatel Superior is located at the Oseberg field centre, and is completely self-sufficient, with all systems functional. The field centre is in the middle of an extremely busy period with substantial work in progress. The flotel is used to provide space for additional personnel. At present, nearly 700 people are at the field centre, including the flotel.

The Oseberg organisation has decided to send personnel from the flotel to land to make room for the personnel from Oseberg A who will be working to bring the facility back on stream. It is primarily personnel in the areas of maintenance, modification and project tasks who will be flown to land. These tasks will not be prioritised as long as the main power supply is down.

Oil and gas production remains shut down. Crews are working hard to restore stable main power supply on board so that the heating unit can be started, personnel can be taken on board, and activities resumed.